The present invention relates to a gasket for an internal combustion engine, particularly a cylinder head gasket and method for forming the same.
The purpose of the cylinder head gasket is to provide a seal between the engine block and the cylinder head to retain liquids such as engine lubricating fluid and engine coolant. The engine block and the cylinder head combine to form combustion chambers, inside which the pistons are displaceably mounted.
Even if the cylinder head gaskets are made with great care, centering of an armor ring relative to the corresponding combustion chamber is not always perfect, especially if allowable manufacturing tolerances for the engine blocks and cylinder heads are taken into account. Furthermore, during engine operation, an increase in temperature is not consistent over the entire surface of the gasket, and thus parasitic stresses may arise due to different expansion at different points in the gasket.
One solution is to totally separate the body of the gasket from the armor rings and then mount the armor rings on the engine block independently of the gasket. However, this solution is unsatisfactory because it greatly increases the number of steps of operation, with the risk of possibly losing the body and the armor rings.
French Patent FR-A-2,446,970 discloses a cylinder head gasket in which the armor ring has a tab engaged in a slot in the gasket body to allow floating mounting of the armor ring. However, reduction to practice is complex and the armor ring is not integral with the body.